"Finally a Lesson" is the thirtieth episode of Season 3 of Teen Titans Go! and the one hundred and thirty-fourth episode overall. It first aired on 28 April 2016 on Cartoon Network.
Robin finally teaches the other Titans a very valuable lesson.
Robin interrupts the Teen Titans while they're relaxing on the couch, noting that they haven't been using the suggestion box. Cyborg and Raven claim they have, but Robin says that writing "Robin Stinks" isn't a suggestion. Beast Boy says that it's true, but Robin tells them to write stuff like "shower more" as that is a suggestion. He tells them that the suggestion box is to provide a thoughtful way to address the flaws in the Teen Titans. He says that someone has put a helpful suggestion which says "Robin should teach more life lessons" but Raven notes it looks like his handwriting. Cyborg and Starfire support the idea of life lessons, but Beast Boy leaves to hang out with cool rollerblading dudes. However, they leave him behind when he refuses to graffiti. Starfire, Raven and Cyborg arrive to comfort him and Beast Boy realizes that his true friends are the one who will always have his back. Cyborg argues and they all pose together in a picture.
However, Robin interrupts by calling their scenario boring and obvious, but Starfire says that Beast Boy learned a lesson. He, however, says that he will be teaching the Titans a real lesson: how to buy rental property as a long term investment. Cyborg doesn't know what rental property means and Robin explains it's a property he buys that other people live in. Beast Boy claims it sounds boring and Robin says that it is, but no one else is teaching the lesson. He says that it's one of the best ways to build equity, which he begins to explain. The other Titans, however, interrupt him as it sounds boring. They begin to leave, but Robin goads them by saying he thought they would like to make money. Raven asks why he didn't say that, but Robin says he did as equity is another word for money. Beast Boy urges him to tell them how to make money, but Robin says they have to buy a property first.
The Titans visit a run-down place where villains live and he explains they'll purchase it in order to make equity. He calls to make an offer and the Titans return to the tower to wait if they accept. After receiving a call, Robin reports that their offer was accepted and Beast Boy celebrates purchasing a building. Robin, however, says they need financing to pay for the property which is $500,000. The Titans begin to freak out, but Robin says that the rent payment would pay for most of it and they need 20% down which $100,000. The Titans begin freaking out again and Robin says that saving up that money will be a lot of hard work and effort. However, he suggests calling someone who has already put in the hard work and effort and calls Batman. The Titans celebrate having 20% percent down, but Starfire asks how they can purchase the property with only that much. He says the rest comes from a bank loan and begins explaining credit.
The Titans complain about the boring process, but Robin says it's all boring. Raven compares the knowledge like a hammer to her skull and Robin says he knows things that will hurt worse. Dogs labeled "Low Credit Score", "Failure to Plan for the Future", and "Not Enough Money to Live After Retirement" attack the Titans until Robin stops them. Robin decides to do something fun and has the Titans fill out paperwork. Beast Boy complains about the lack of direction and Raven says that it better end fighting someone. Robin says it won't as they're only learning important information, but reassures that there will be a satisfying end.
In front of their rental property, Robin congratulates the Titans for their purchase and says it will be making them money. He receives a call from Brother Blood demanding that they fix his toilet. Beast Boy tells Robin to tell Brother Blood to fix it himself, but Robin says that because they're his landlords, they have to fix it. Raven asks what would happen if they refuse and Robin explains he can withhold his rent money and they'll lose equity. Robin orders the Titans to maintain the quality of the building. Beast Boy fixes Brother Blood's toilet, Raven fixes Control Freak's sink, Cyborg tries to unlock a door for Mumbo Jumbo, Starfire changes a light bulb for Doctor Light, and Robin kills cockroaches for Punk Rocket. That night, Robin reveals to the Titans that he discovered the building is rent-controlled. He explains that the tenants are paying the low market value for the apartments and Raven suggests evicting them. Robin says it's illegal as renters have rights and suggests getting them to leave on their own. He tells the villains they are being criminals for paying the low market value and has the Titans teach them about the justice of a free market, ordering them to evict.
After the villains are gone, the Titans put up "For Rent" signs on their property. Raven says they can raise the rent back up to market value and Beast Boy celebrates becoming rich. Robin explains that it takes decades to build equity, but that in thirty years, they will have moderate cash flow to pay for their medication when they turn old. The cool rollerblading dudes notice the property as a cool place to hang and give the Titans money which they throw into the air.
Robin ends the episode by telling the viewers to visit a library or ask their local realtor to learn more information about investing in rental property.
For a full transcript of "Finally a Lesson", click here.